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1.
J Colloid Interface Sci ; 677(Pt A): 68-78, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39083893

RESUMO

Carbon/metal composites derived from metal-organic frameworks (MOFs) have attracted widespread attention due to their excellent electronic conductivity, adjustable porosity, and outstanding stability. However, traditional synthesis methods are limited by the dense stereo geometry and large crystal grain size of MOFs, resulting in many metals active sites are buried in the carbon matrix. While the common strategy involves incorporating additional dispersed media into material, this leads to a decrease in practical metal content. In this study, nanosized copper-metal-organic frameworks (Cu-MOFs) are in-situ grown on surface of carbon spheres by pre-anchoring copper ions, and the hybrid composite of porous carbon/copper oxide with high copper atom utilization rate is prepared through activation and pyrolysis methods. This strategy effectively addresses the issue of insufficient exposure of metal sites, and the obtained composite material exhibits high effective copper atom utilization rate, large specific surface area (2052.3 m2·g-1), diverse pore structure, outstanding specific capacity (1076.5F·g-1 at 0.5 A·g-1), and excellent cycle stability. Furthermore, this highly atom-economical universal method has positive significance in application fields of catalysis, energy storage, and adsorption.

2.
J Colloid Interface Sci ; 677(Pt A): 697-703, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39116567

RESUMO

The correlation between structural transformation and optical characteristics of cesium lead bromide (CsPbBr3) nanocrystals (NCs) suggests insights into their growth mechanism and optical performance. Systematic control of reaction parameters led to the successful fabrication of on-demand shape-morphing CsPbBr3 NCs. Transmission electron microscopy observations showed that the shape transformation from nanocubes to microcrystals could be accelerated by increasing the precursor:ligand molar ratio and reaction time. Further evidence for orthorhombic CsPbBr3 NCs was obtained from their selected-area electron diffraction pattern, which exhibits a twin domain induced by the presence of large NCs. Likewise, we observed a substantial decrease in photoluminescence (PL) intensity of CsPbBr3 due to surface decomposition or surface ligand loss resulting from increased size. In addition, fusion of smaller particles having other dimensionality induced the increase in the PL full-width at half maximum. In particular, existence of larger bulk material caused a reduction in the peak intensity in the absorption spectra and a trend of decreasing tendency in intensity of the absorption bands related to bromoplumbate species provided direct evidence of fully converted Cs-oleate.

3.
J Colloid Interface Sci ; 677(Pt A): 632-644, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39116561

RESUMO

Cartilage is severely limited in self-repair after damage, and tissue engineering scaffold transplantation is considered the most promising strategy for cartilage regeneration. However, scaffolds without cells and growth factors, which can effectively avoid long cell culture times, high risk of infection, and susceptibility to contamination, remain scarce. Hence, we developed a cell- and growth factor-dual free hierarchically structured nanofibrous sponge to mimic the extracellular matrix, in which the encapsulated core-shell nanofibers served both as mechanical supports and as long-lasting carriers for bioactive biomass molecules (glucosamine sulfate). Under the protection of the nanofibers in this designed sponge, glucosamine sulfate could be released continuously for at least 30 days, which significantly accelerated the repair of cartilage tissue in a rat cartilage defect model. Moreover, the nanofibrous sponge based on carboxymethyl chitosan as the framework could effectively fill irregular cartilage defects, adapt to the dynamic changes during cartilage movement, and maintain almost 100 % elasticity even after multiple compression cycles. This strategy, which combines fiber freeze-shaping technology with a controlled-release method for encapsulating bioactivity, allows for the assembly of porous bionic scaffolds with hierarchical nanofiber structure, providing a novel and safe approach to tissue repair.


Assuntos
Cartilagem Articular , Quitosana , Glucosamina , Nanofibras , Alicerces Teciduais , Quitosana/química , Quitosana/análogos & derivados , Animais , Nanofibras/química , Cartilagem Articular/efeitos dos fármacos , Ratos , Glucosamina/química , Glucosamina/análogos & derivados , Alicerces Teciduais/química , Engenharia Tecidual , Ratos Sprague-Dawley , Tamanho da Partícula , Porosidade , Propriedades de Superfície
4.
J Colloid Interface Sci ; 677(Pt A): 885-894, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39126807

RESUMO

Zinc metal anodes encounter significant challenges, including dendrite growth, hydrogen evolution, and corrosion, all of which impede the rate capability and longevity of aqueous zinc-ion batteries (AZIBs). To effectively tackle these issues, we introduced Tween-80 into the traditional ZnSO4 electrolyte as an additive. Tween-80 possesses electronegative oxygen atoms that enable it to adsorb onto the zinc (Zn) anode surface, facilitating the directional deposition of Zn metal along the (002) orientation. The hydroxyl and ether groups within Tween-80 can displace some of the coordinated water molecules in the Zn2+ inner solvation shell. This disruption of the hydrogen bond network regulates the solvation structure of Zn2+ ions and suppresses the possibility of hydrogen evolution. Moreover, the long hydrocarbon chain present in Tween-80 exhibits excellent hydrophobic properties, aiding in the resistance against corrosion of the Zn anode by water molecules and reducing hydrogen evolution. Consequently, a symmetric cell equipped with the Tween-80 additive can cycle stably for over 4000 h at 1 mA cm-2 and 1 mA h cm-2. When paired with the V2O5 cathode, the full cell demonstrates a high-capacity retention rate exceeding 80 % over 1000 cycles at a current density of 2 A g-1. This study underscores the advantages of utilizing non-ionic surfactants for achieving high-performance aqueous zinc-ion batteries.

5.
Clin Chim Acta ; 564: 119901, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-39134218

RESUMO

BACKGROUND: Platelet contains growth factors that enhance tissue repair mechanisms, including epidermal growth factor (EGF), platelet-derived growth factor (PDGF-AA and -AB), and transforming growth factor (TGF)-ß. Autologous platelet-rich plasma (PRP) has been shown to significantly improve the treatment of tendon injuries compared with hyaluronic acid and placebo. The topic of agreement between platelet concentrations and growth factors has been covered in some previous studies, but growth factor levels did not correlate well with platelet concentrations. METHOD: In this study, autologous PRP was prepared by concentrating platelets through a J6-MI centrifuge. The automatic hematology analyzer Sysmex XN-20 was used to analyze the platelet concentration in PRP, and the PRP growth factors were determined by ELISA, including PDGF, transforming growth factor- ß1 (TGF-ß1), and EGF. Statistical analysis was conducted on data from 107 patients who received autologous PRP using Pearson correlation analysis. RESULTS: Pearson correlation analysis revealed PDGF, TGF, and EGF had a strong positive correlation with the platelet concentration of the final PRP product (r = 0.697, p < 0.0001; r = 0.488, p < 0.0001; r = 0.572, p < 0.0001, respectively) CONCLUSIONS: There was a strong positive correlation between the concentration of platelets in the final PRP product and the levels of PDGF-AB, TGF-ß, and EGF. These results suggested straightforward and cost-effective growth factor tests can provide valuable information about platelet content in PRP.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular , Plasma Rico em Plaquetas , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Contagem de Plaquetas , Plasma Rico em Plaquetas/metabolismo , Plasma Rico em Plaquetas/química
6.
Biomaterials ; 313: 122777, 2025 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39222545

RESUMO

Telomere length plays a crucial role in cellular aging and the risk of diseases. Unlike normal cells, cancer cells can extend their own survival by maintaining telomere stability through telomere maintenance mechanism. Therefore, regulating the lengths of telomeres have emerged as a promising approach for anti-cancer treatment. In this study, we introduce a nanoscale octopus-like structure designed to induce physical entangling of telomere, thereby efficiently triggering telomere dysfunction. The nanoscale octopus, composed of eight-armed PEG (8-arm-PEG), are functionalized with cell penetrating peptide (TAT) to facilitate nuclear entry and are covalently bound to N-Methyl Mesoporphyrin IX (NMM) to target G-quadruplexes (G4s) present in telomeres. The multi-armed configuration of the nanoscale octopus enables targeted binding to multiple G4s, physically disrupting and entangling numerous telomeres, thereby triggering telomere dysfunction. Both in vitro and in vivo experiments indicate that the nanoscale octopus significantly inhibits cancer cell proliferation, induces apoptosis through telomere entanglement, and ultimately suppresses tumor growth. This research offers a novel perspective for the development of innovative anti-cancer interventions and provides potential therapeutic options for targeting telomeres.


Assuntos
Apoptose , Telômero , Telômero/metabolismo , Apoptose/efeitos dos fármacos , Humanos , Animais , Linhagem Celular Tumoral , Camundongos , Quadruplex G/efeitos dos fármacos , Camundongos Nus , Polietilenoglicóis/química , Proliferação de Células/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Neoplasias/patologia , Neoplasias/tratamento farmacológico , Feminino , Peptídeos Penetradores de Células/química , Peptídeos Penetradores de Células/farmacologia , Nanoestruturas/química
7.
J Clin Exp Hepatol ; 15(1): 102402, 2025.
Artigo em Inglês | MEDLINE | ID: mdl-39296665

RESUMO

Background: The growth hormone-insulin-like growth factor (GH-IGF-1) axis and its impairment with sarcopenia, frailty, bone health, complications, and prognosis are not well characterized in cirrhosis. Methods: We investigated the adult decompensated cirrhosis out-patients at a tertiary care institute between 2021 and 2023 for serum GH and IGF-1 levels, and associated them with sarcopenia (CT-SMI in cm2/m2), liver frailty index (LFI), osteodystrophy (DEXA), clinical decompensations (overall, ascites, encephalopathy, infection, and bleed), and survival up to 180 days. Results: One-hundred-seventy-two patients, 95% males, aged 46.5 years (median). logIGF-1 levels were negatively associated with sarcopenia, osteodystrophy, LFI, CTP, and MELD-Na score (P < 0.05 each). Patients with low IGF-1 levels had a higher incidence of complications (overall, ascites and encephalopathy) than those with intermediate, and high IGF-1 levels (P < 0.05 each). Both logIGF-1 (AUC: 0.686) and MELD (AUC: 0.690) could predict 180-day mortality (P < 0.05, each). Adding logIGF-1 with MELDNa further improved discriminative accuracy of MELDNa (AUC: 0.729) P < 0.001. The increase in IGF-1 on follow-up was associated with better survival and fewer complications. Conclusion: Reduced IGF-1 levels reflect sarcopenia, frailty, and osteodystrophy in cirrhosis. Low IGF-1 are associated with severity, development of decompensations, and mortality.

8.
J Colloid Interface Sci ; 678(Pt C): 346-358, 2025 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-39298987

RESUMO

In recent years, core-shell structured Prussian Blue Analogues (PBAs) have been considered as highly promising cathode materials for sodium-ion batteries. Reducing production costs and simplifying the preparation method for core-shell PBAs have also become crucial considerations. This paper presents a novel approach for the first time: by acid-treating the as-synthesized solution from a simple coprecipitation reaction, a high-crystallinity, sodium-rich Mn2+-doped iron hexacyanoferrate (Fe/MnHCF) shell material is self-grown on the surface of manganese hexacyanoferrate (MnHCF). This method significantly improves the electrochemical properties of the MnHCF material. The core-shell structured PBA exhibits excellent cycling performance (with a capacity retention of 95.5 % for 400 cycles at 1 A/g) and high rate performance (134.2mAh/g@10 mA/g, 95.2mAh/g@1 A/g). In this article, we explore the growth mechanism of the high-sodium content, high-crystallinity shell structure and introduce a green chelating agent that is better suited for the crystallization of Mn and Fe-type PBA systems. Our study demonstrates that Mn2+ doping enhances the conductivity of the shell material. Meanwhile, the heterojunction structure of MnHCF@Fe/MnHCF conducive to charge separation and migration. This straightforward synthesis strategy offers a novel approach for fabricating high-performance core-shell structured Prussian Blue Analogue materials.

9.
J Colloid Interface Sci ; 678(Pt C): 959-967, 2025 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-39326167

RESUMO

This study demonstrates the preparation of needle-like Ce-MOF crystals on molybdenum disulfide (MoS2) nanosheets using in-situ growth technology. This hybrid structure significantly enhances the thermal management and mechanical properties of thermosetting epoxy resin (EP). Specifically, EP/Ce-MOF@MoS2-3 exhibits a notable increase in tensile strength (TS) to 50.87 MPa and elongation at break (EB) to 10.84 %. Moreover, Ce-MOF@MoS2 provides synergistic flame retardant benefits, reducing the peak heat release rate (pHRR) and total heat release (THR) of EP/Ce-MOF@MoS2-3 by 38 % and 12.64 %, respectively, compared to EP-0. Additionally, Ce-MOF@MoS2 suppresses smoke and reduces toxic emissions; at a 3 % loading, it decreases CO and CO2 production in EP nanocomposites by 48.8 % and 38.7 %, respectively. Thus, this Ce-MOF@MoS2 hybrid, synthesized via in-situ growth, offers a novel approach for developing EP nanocomposites with superior thermal management and mechanical properties, along with effective flame retardancy and reduced hazardous emissions during thermal events.

10.
J Environ Sci (China) ; 148: 375-386, 2025 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39095172

RESUMO

Tuojiang River Basin is a first-class tributary of the upper reaches of the Yangtze River-which is the longest river in China. As phytoplankton are sensitive indicators of trophic changes in water bodies, characterizing phytoplankton communities and their growth influencing factors in polluted urban rivers can provide new ideas for pollution control. Here, we used direct microscopic count and environmental DNA (eDNA) metabarcoding methods to investigate phytoplankton community structure in Tuojiang River Basin (Chengdu, Sichuan Province, China). The association between phytoplankton community structure and water environmental factors was evaluated by Mantel analysis. Additional environmental monitoring data were used to pinpoint major factors that influenced phytoplankton growth based on structural equation modeling. At the phylum level, the dominant phytoplankton taxa identified by the conventional microscopic method mainly belonged to Bacillariophyta, Chlorophyta, and Cyanophyta, in contrast with Chlorophyta, Dinophyceae, and Bacillariophyta identified by eDNA metabarcoding. In α-diversity analysis, eDNA metabarcoding detected greater species diversity and achieved higher precision than the microscopic method. Phytoplankton growth was largely limited by phosphorus based on the nitrogen-to-phosphorus ratios > 16:1 in all water samples. Redundancy analysis and structural equation modeling also confirmed that the nitrogen-to-phosphorus ratio was the principal factor influencing phytoplankton growth. The results could be useful for implementing comprehensive management of the river basin environment. It is recommended to control the discharge of point- and surface-source pollutants and the concentration of dissolved oxygen in areas with excessive nutrients (e.g., Jianyang-Ziyang). Algae monitoring techniques and removal strategies should be improved in 201 Hospital, Hongrihe Bridge and Colmar Town areas.


Assuntos
Monitoramento Ambiental , Fitoplâncton , Rios , Rios/química , China , Poluentes Químicos da Água/análise , Fósforo/análise
11.
Arq. bras. oftalmol ; Arq. bras. oftalmol;88(2): e2023, 2025. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1574013

RESUMO

ABSTRACT Purpose: To compare the outcomes of intravitreal dexamethasone implant used as either an adjuvant or a switching therapy for diabetic macular edema in patients with poor anatomic response after three consecutive monthly injections of ranibizumab. Methods: This retrospective study included patients with diabetic macular edema who received three consecutive doses of ranibizumab as initial therapy and demonstrated poor response. A single dose of intravitreal de xamethasone implant was administered to these patients. The patients were divided into two groups according to the treatment modalities: the adjuvant therapy group, consisting of patients who continued treatment with ranibizumab injection after receiving intravitreal dexamethasone implant, and the switch therapy group, consisting of patients who were switched from ranibizumab treatment to intravitreal dexamethasone implant as needed. The main outcome measurements were best corrected visual acuity and central retinal thickness at baseline and at 3, 6, 9, and 12 months of follow-up. Results: In this study that included 64 eyes of 64 patients, the best corrected visual acuity and central retinal thickness values did not significantly differ between the groups at baseline and at 6 months of follow-up (p>0.05). However, at 12 months, the best corrected visual acuity values in the adjuvant and switch therapy groups were 0.46 and 0.35 LogMAR, respectively (p=0.012), and the central retinal thickness values were 344.8 and 270.9, respectively (p=0.007). Conclusions: In a real-world setting, it seems more reasonable to use intravitreal dexamethasone implant as a switch therapy rather than an adjuvant therapy for diabetic macula edema refractory to ranibizumab despite three consecutive monthly injections of ranibizumab. Patients switched to intravitreal dexamethasone implant were found to have better anatomic and visual outcomes at 12 months than those who continued ranibizumab therapy despite their less-than-optimal responses.

12.
Nano Lett ; 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39485017

RESUMO

Due to their flexible geometry, in-plane selective area grown (SAG) nanowires (NWs) encompass the advantages of vapor-liquid-solid NWs and planar structures. The complex interplay of growth kinetics and NW dimensions provides new pathways for crystal engineering; however, their growth mechanisms remain poorly understood. We analyze the growth mechanisms of GaAs(Sb) and InGaAs/GaAs(Sb) in-plane SAG NWs using molecular beam epitaxy (MBE). While GaAs(Sb) NWs consistently follow a layer-by-layer growth, the InGaAs/GaAs(Sb) growth transitions from step-flow to layer-by-layer and layer-plus-island depending on the InGaAs thickness and the NW dimensions. We extract the diffusion lengths of Ga adatoms along the [11̅0] and [110] directions under As2 during GaAs(Sb) growth. Our results indicate that Sb may inhibit the layer-by-layer to step-flow transition. Our findings show that different growth modes can be achieved in the MBE of in-plane SAG NWs grown on the same substrate and highlight the importance of the interplay with NW dimensions.

13.
J Anim Breed Genet ; 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39485039

RESUMO

Understanding the genetic basis of growth and metabolic traits in sheep is crucial for improving production efficiency and sustainability. The current study aimed to estimate the genetic influences, both direct and maternal, on growth rate and Kleiber's ratio traits in Harnali sheep using pedigree data under Bayesian inference. The data pertained to 2404 animals spanned over 24 years (1998-2021). Fixed factors such as birth period, lamb sex and dam's weight at lambing were considered. The traits studied included average daily gains (ADGs) categorised into ADG1 (birth to weaning age), ADG2 (weaning to 6 months of age) and ADG3 (6-12 months of age), as well as corresponding Kleiber's ratios (KR1, KR2 and KR3). Six single-trait animal models were employed to estimate covariance components and heritabilities, integrating direct additive and maternal effects alongside significant fixed factors using THRGIBBS1F90 and POSTGIBBSF90 programmes. Direct heritability estimates were obtained for ADG1 (0.11 ± 0.05), ADG2 (0.06 ± 0.03), ADG3 (0.03 ± 0.03), KR1 (0.07 ± 0.03), KR2 (0.06 ± 0.03) and KR3 (0.05 ± 0.03). Maternal genetic effects have contributed significant particularly to pre-weaning traits. The study identified an antagonistic relationship between direct additive and maternal genetic effects. Positive genetic and phenotypic correlations emphasised the intricate relationship between growth and metabolic efficiency in Harnali sheep. The current study offers critical insights into the genetic basis of growth and metabolic traits in Harnali sheep, ultimately contributing to more efficient and sustainable sheep production systems.

14.
Artigo em Inglês | MEDLINE | ID: mdl-39482414

RESUMO

Microplastics have polluted agricultural soils, posing a substantial risk to crop productivity. Moreover, the presence of microplastic pollution has caused a disturbance in the composition of the microbial community in the soil surrounding plant roots, therefore impacting the growth of beneficial bacteria. A study was conducted to examine if humic acid (HA) can counteract the harmful effects of microplastics (MPs) on the growth of black gram crops and the composition of the rhizosphere soil microbial community, to reduce the negative impacts of microplastics on these microorganisms and crops. The research was carried out using mud pots and the plastic utilized for the experiment consisted of 60% high-density polyethylene (HDPE) and 40% polypropylene (PP). The soil was enriched with lignite-based potassium humate, which had a pH range of 8.0-9.5 and with 65% humic acid. The experiment consisted of six treatments: T1, which served as the control without HA and MP; T2, which involved the use of HA at a concentration of 0.15% w/w; T3, which involved the use of MP at a concentration of 0.2% w/w; T4, which involved the use of MP at a concentration of 0.4% w/w; T5, which involved the combination of HA at a concentration of 0.15% w/w and MP at a concentration of 0.2% w/w; and T6, which involved the combination of HA at a concentration of 0.15% w/w and MP at a concentration of 0.4% w/w. The plant growth characteristics, including germination percentage, nodule number, and chlorophyll content, were measured. In addition, the DNA obtained from the rhizosphere soil was analyzed using metagenomics techniques to investigate the organization of the microbial population. Seedlings in soil polluted with MP exhibited delayed germination compared to seedlings in uncontaminated soil. Following 60 days of growth, the soil samples treated with T5 (0.2% MP and 0.15% HA w/w) had the highest population of bacteria and rhizobium, with counts 5.58 ± 0.02 and 4.90 ± 0.02 CFU g-1 soil. The plants cultivated in T5 had the most elevated chlorophyll-a concentration (1.340 ± 0.06 mg g-1), and chlorophyll-b concentration (0.62 ± 0.02 mg g-1) while those cultivated in T3 displayed the lowest concentration of chlorophyll-a (0.59 ± 0.02 mg g-1) and chlorophyll-b (0.21 ± 0.04 mg g-1). Within the phylum, Proteobacteria had the highest prevalence in all treatments. However, when the soil was polluted with MPs, its relative abundance was reduced by 8.4% compared to the control treatment (T1). Conversely, treatment T5 had a 3.76% rise in relative abundance when compared to treatment T3. The predominant taxa found in soil polluted with MP were Sphingomonas and Bacillus, accounting for 19.3% of the total. Sphingomonas was the predominant genus (21.2%) in soil polluted with MP and supplemented with humic acid. Humic acid can be used as a soil amendment to mitigate the negative effects of MPs and enhance their positive advantages. Research has demonstrated that incorporating humic acid into soil is a viable method for maintaining the long-term integrity of soil's physical, chemical, and biological characteristics.

15.
Arch Pharm Res ; 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39482441

RESUMO

Human antigen R (HuR), an RNA-binding protein, is implicated in regulating mRNA stability and translation in cancer, especially in triple-negative breast cancer (TNBC), a highly aggressive form. CRISPR/Cas9-mediated HuR knockout (HuR CRISPR) presents a promising genetic therapeutic approach, but it encounters transfection limitations. Docetaxel (DTX), an effective cytotoxic agent against metastatic breast cancer (BC), faces challenges related to vehicle-associated adverse events in DTX formulations. Therefore, we designed multifunctional nanoparticles with pH-sensitive PEG derivatives and targeting peptides to enable efficient HuR CRISPR and DTX delivery to human TNBC MDA-MB-231 cells and tumor-bearing mice. Our findings indicated that these nanoparticles displayed pH-responsive cytotoxicity, precise EGFR targeting, efficient tumor penetration, successful endosomal escape, and accurate nuclear and cytoplasmic localization. They also demonstrated the ability to spare normal cells and prevent hemolysis. Our study concurrently modulated multiple pathways, including EGFR, Wnt/ß-catenin, MDR, and EMT, through the regulation of EGFR/PI3K/AKT, HuR/galectin-3/GSK-3ß/ß-catenin, and P-gp/MRPs/BCRP, as well as YAP1/TGF-ß/ZEB1/Slug/MMPs. The combined treatment arrested the cell cycle at the G2 phase and inhibited EMT, effectively impeding tumor progression. Tissue distribution, biochemical assays, and histological staining revealed the enhanced safety profile of pH-responsive PEG- and peptide-modified nanoformulations in TNBC mice. The DTX-embedded and peptide-modified nanoparticles mitigated the side effects of DTX, enhanced cytotoxicity in TNBC MDA-MB-231 cells, and exhibited remarkable antitumor efficacy and safety in TNBC-bearing mice with HuR CRISPR deletion. Collectively, the combination therapy of DTX and CRISPR/Cas9 offers an effective platform for delivering antineoplastic agents and gene-editing systems to combat tumor resistance and progression in TNBC.

16.
Stem Cell Res Ther ; 15(1): 388, 2024 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-39482744

RESUMO

BACKGROUND: Critical limb ischemia (CLI) is a condition characterized by insufficient blood flow to the lower limbs, resulting in severe ischemia and potentially leading to amputation. This study aims to identify novel vasculogenic precursor cells (VPCs) in human bone marrow and evaluate their efficacy in combination with bone marrow-derived mesenchymal stem cells (BM-MSCs) for the treatment of CLI. METHODS: Ex vivo cultured VPCs and BM-MSCs from bone marrow were characterized and their effects on neovascularization and long-term tissue regeneration were tested in a mouse CLI model. RESULTS: VPCs, expressing high levels of hepatocyte growth factor and c-MET, were identified from human bone marrow aspirates. These cells exhibited strong vasculogenic capacity in vitro but possessed a cellular phenotype distinct from those of previously reported endothelial precursor cells in circulation or cord blood. They also expressed most surface markers of BM-MSCs and demonstrated multipotent differentiation ability. Screening of 376 surface markers revealed that VPCs uniquely display CD141 (thrombomodulin). CD141+VPCs are present in BM aspirates as a rare population and can be expanded ex vivo with a population doubling time of approximately 20 h, generating an elaborate vascular network even under angiogenic factor-deficient conditions and recruiting BM-MSCs to the network as pericyte-like cells. Intramuscular transplantation of a combination of human CD141+VPCs and BM-MSCs at a ratio of 2:1 resulted in limb salvage, blood flow recovery, and regeneration of large vessels in the femoral artery-removed CLI model, with an efficacy superior to that of singular transplantation. Importantly, large arteries and arterioles in dual cell transplantation expressed human CD31 in the intima and human α-smooth muscle actin in media layer at 4 and 12 weeks, likely indicating their lineage commitment to endothelial cells and vascular smooth muscle, respectively, in vivo. CONCLUSION: Dual-cell therapy using BM-derived CD141+ VPCs and BM-MSCs holds potential for further development in clinical trials to treat peripheral artery disease and diabetic ulcers.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Neovascularização Fisiológica , Humanos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Animais , Camundongos , Transplante de Células-Tronco Mesenquimais/métodos , Células da Medula Óssea/metabolismo , Células da Medula Óssea/citologia , Diferenciação Celular , Masculino , Isquemia/terapia , Isquemia/metabolismo , Células Cultivadas
17.
Ultrasound Obstet Gynecol ; 64(5): 651-660, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39482803

RESUMO

OBJECTIVE: To identify prenatal predictors of poor perinatal outcome in fetuses with isolated sacrococcygeal teratoma (SCT). METHODS: This was a retrospective study of fetuses with isolated (non-syndromic) SCT managed at one of five pediatric surgery and/or fetal medicine centers between January 2007 and December 2017. The primary outcome was the occurrence of poor perinatal outcome, defined as prenatal death (including termination), or neonatal death or severe compromise (hemorrhagic shock). Data regarding prenatal diagnosis (sonographic features both at referral and at the last ultrasound examination before pregnancy outcome, assessment of SCT growth velocity), perinatal complications and outcome, and neonatal course were analyzed to determine prenatal SCT characteristics associated with adverse perinatal outcome. RESULTS: Fifty-five fetuses were included, diagnosed with isolated SCT at a median gestational age of 22 (interquartile range, 18-23) weeks. There was a poor perinatal outcome in 31% (n = 17) of these cases, including intrauterine fetal demise (4%, n = 2), pregnancy termination (13%, n = 7) and neonatal severe compromise (15%, n = 8), leading to neonatal death in five cases. The overall survival rate after prenatal diagnosis of isolated SCT was 75% (n = 41 of 55). Earlier gestational age at diagnosis (P = 0.02), large tumor volume at referral (P < 0.001), presence of one or more hemodynamic complications (P = 0.02), fast tumor growth velocity (P < 0.001) and high tumor grade (highest tumor grade ≥ 3) (P = 0.049) were associated with poor perinatal outcome on univariate analysis. On stepwise logistic regression analysis, tumor growth velocity was the only remaining independent factor associated with poor perinatal outcome (odds ratio (OR) (per 1-mm/week increase), 1.48 (95% CI, 1.22-1.97), P = 0.001). The best predictive cut-off of tumor growth velocity for poor perinatal outcome was 7 mm/week (OR, 25.7 (95% CI, 5.6-191.3), P < 0.001), yielding a sensitivity of 88% and a specificity of 77%. CONCLUSIONS: Approximately 30% of fetuses with a diagnosis of isolated SCT have poor perinatal outcome. Tumor growth velocity ≥ 7 mm/week appears to be an appropriate discriminative cut-off for poor perinatal outcome. These results could help to inform prenatal management and counseling of parents with an affected pregnancy. © 2024 The Author(s). Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Idade Gestacional , Região Sacrococcígea , Teratoma , Ultrassonografia Pré-Natal , Humanos , Feminino , Teratoma/diagnóstico por imagem , Teratoma/embriologia , Teratoma/mortalidade , Gravidez , Estudos Retrospectivos , Região Sacrococcígea/diagnóstico por imagem , Região Sacrococcígea/embriologia , Recém-Nascido , Adulto , Resultado da Gravidez , Morte Fetal/etiologia , Mortalidade Perinatal , Morte Perinatal , Doenças Fetais/diagnóstico por imagem , Doenças Fetais/mortalidade
18.
Physiol Rep ; 12(21): e70112, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39482843

RESUMO

Preeclampsia (PE) is characterized by de novo hypertension (HTN) and is often associated with intrauterine growth restriction (IUGR). Hallmarks of PE are placental ischemia, decreased nitric oxide (NO) bioavailability, oxidative stress (OS), and organ damage in the kidneys and brain. This study aims to characterize a new model of PE using pregnant IUGR rats from hypertensive placental ischemic dams. It is hypothesized that pregnant IUGR rats from hypertensive placental ischemic dams will have elevated blood pressure (BP), OS, and organ damage. In this study, pregnant rats are divided into two groups: normal pregnant (NP) and hypertensive placental ischemic dams (RUPP). Offspring from NP and RUPP dams were mated at 10 weeks of age to generate pregnant IUGR (IUGR Preg) and pregnant control (CON Preg) rats. BP and other markers of PE were evaluated during late gestation. Pregnant IUGR rats had elevated BP and systemic OS. The maternal body weight of pregnant IUGR rats and their pups' weights were decreased, while the brains were enlarged with elevated OS. In summary, pregnant IUGR rats, born from hypertensive placental ischemic dams, have HTN and increased systemic and brain OS, with larger brain sizes and smaller pups. Furthermore, this study shows that pregnant IUGR rats exhibit a preeclamptic-like phenotype, suggesting a new epigenetic model of PE.


Assuntos
Modelos Animais de Doenças , Retardo do Crescimento Fetal , Placenta , Pré-Eclâmpsia , Animais , Gravidez , Feminino , Retardo do Crescimento Fetal/patologia , Retardo do Crescimento Fetal/fisiopatologia , Retardo do Crescimento Fetal/metabolismo , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/fisiopatologia , Pré-Eclâmpsia/patologia , Ratos , Placenta/metabolismo , Placenta/patologia , Placenta/irrigação sanguínea , Estresse Oxidativo , Ratos Sprague-Dawley , Isquemia/metabolismo , Isquemia/patologia , Isquemia/fisiopatologia , Pressão Sanguínea , Encéfalo/metabolismo , Encéfalo/patologia
19.
Anim Biosci ; 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39483036

RESUMO

Objective: The current study aimed to investigate the effect of dietary supplementation of xylanase alone or combination of xylanase and ß-glucanase in high non-starch polysaccharides (NSP) diets with low energy on growth performance, meat quality, intestinal measurements, stress responses, and energy and nutrient utilization in broiler chickens. Methods: A total of four hundred 8-d-old Ross 308 broiler chickens were randomly allotted to 1 of 4 treatment groups with 10 replicates. A positive control (PC) diet was formulated with adequate energy and nutrients, whereas a negative control (NC) diet had 100 kcal/kg less AMEn than the PC diet with increasing inclusion of high NSP ingredients. Two additional diets were produced by supplementing 0.1% xylanase alone or 0.1% xylanase and ß-glucanase mixture in the NC diet. Experiments lasted for 27 d. Results: Birds fed PC diets had less (p<0.05) FCR than those fed NC diets. Birds fed NC diets supplemented with xylanase alone or combination of xylanase and ß-glucanase had less (p<0.05) FCR than those fed NC diets. Dietary supplementation of xylanase alone in NC diets exhibited the highest (p<0.05) breast meat pH among dietary treatments. Birds fed PC diets or NC diets supplemented with xylanase and ß-glucanase combination exhibited greater (p<0.05) VH:CD ratio than those fed NC diets. Dietary supplementation of xylanase alone and combination of xylanase and ß-glucanase in NC diets decreased (p<0.05) ileal digesta viscosity and increased (p<0.05) xylo-oligosaccharide concentrations in the gastrointestinal tract (GIT) compared with NC diets without affecting energy and nutrient utilization in NC diets. Conclusion: Dietary supplementation of xylanase in high NSP diets with low energy concentrations improves growth performance by decreasing digesta viscosity and increasing concentrations of xylo-oligosaccharides in the GIT of broiler chickens. However, little additional benefits of ß-glucanase supplementation in combination with xylanase are identified for broiler chickens.

20.
Math Biosci Eng ; 21(8): 6870-6897, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39483097

RESUMO

Chemical heterogeneity significantly influences the dynamics of phytoplankton and zooplankton interactions through its effects on phytoplankton carrying capacity and zooplankton ingestion rates. Our central objective of this study was to develop and examine a nonautonomous model of phytoplankton-zooplankton growth, which incorporates season-driven variations in light intensity and chemical heterogeneity. The dynamics of the system is characterized by positive invariance, dissipativity, boundary dynamics, and internal dynamics. Subsequently, numerical simulations were conducted to validate the theoretical findings and to elucidate the effects of seasonal light intensity, nutrient availability, and zooplankton loss rates on phytoplankton dynamics. The outcomes of our model and analysis offer a potential explanation for seasonal phytoplankton blooms.


Assuntos
Simulação por Computador , Luz , Modelos Biológicos , Fitoplâncton , Estações do Ano , Zooplâncton , Fitoplâncton/crescimento & desenvolvimento , Fitoplâncton/fisiologia , Fitoplâncton/efeitos da radiação , Zooplâncton/fisiologia , Animais , Eutrofização , Ecossistema , Biomassa , Dinâmica Populacional , Cadeia Alimentar
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